The invention relates to processes for stripping magnetic media off of a disk.
In the past, disk stripping was typically done using mechanically driven brushes and solvents. In some cases, a light grinding operation has been necessary. Shortcomings of this process include: excessive and time consuming handling of the disks; the additional costs of materials, labor and process equipment; and contamination of the disk from the stripping solvents.
Alternatively, the disk can be stripped using a solvent spray wash while the disk is still on the coating machine. According to this method, while the disk is rotated at relatively high speed (approximately 2,000 rpm), a short spray of acetone is directed at the inside diameter of the disk, with the operator then immediately wiping the entire surface of the disk with a lint free cloth, saturated with acetone. Some shortcomings of this process are that: when the acetone spray is directed at the inside diameter of the disk, some of the acetone invariably leaks under the hub cover and flows to the other side of the disk causing a partial stripping of the coating on the opposite side of the disk; acetone contamination of the disk often results; small water droplets can form on the surface of the disk due to condensation resulting from excessive cooling of the disk during acetone evaporation, with these water droplets causing coating runs and streaks; and the wiping operation can itself scratch the disk surface.